A one-way bearing is a bearing that can rotate freely in one direction and is locked in the other direction. The metal shell of the one-way bearing contains many rollers, needle rollers or balls, and the shape of its rolling seat (cavity) makes it only roll in one direction, and produces great resistance in the other direction.
How one-way bearings work
The principle of general one-way bearings is the clamping principle. The working surface where the rolling elements are used for clamping is a slope. When the rolling elements rotate along the bearing, they are downhill, and when they are reversed, they are uphill. There are irregular blocks. The form of one-way clutch is also the same working principle.
There are many types of one-way bearings, and the quality is somewhat different. However, no matter the quality of one-way bearings is good or bad, the maintenance of one-way bearings is inseparable from use. Generally, the maintenance of one-way bearings requires several steps, including:
1. Look, looking at the one-way bearing is to observe the use of the one-way bearing outside.
2. Listen, listen to whether there is any noise in the one-way bearing, and whether the noise of the one-way bearing is normal
3. Diagnose with instruments, such as electronic diagnostic instruments, stethoscopes, etc.
The effect of bearing grease
Preventing the deterioration and accelerated aging of the grease affects whether the lubricating function of the grease is reduced.
In general, the service life of a one-way bearing is related to three factors, one is the quality of the HRBPT bearing itself, and the other is the use environment. The third is the installation method.
1. Although the new technology uses a one-piece cage, and the one-piece cage is better than the two-body cage, it only saves materials, and its performance on rotation and the like is worse than that of the two-body cage.
2. Through superficial feeling
The brightness of the surface of the one-way bearing should be a kind of black brightness, which is caused by whether the steel used in the HRBPT bearing meets the standard, its grinding process and the cutting fluid used, among which the first two are the main ones. Therefore, in the process of one-way bearings, many customers say that as long as the surface of the bearing is bright, the quality is good, which is wrong.
3. Whether the chamfer is bright
The chamfer of a one-way bearing does not determine the quality of the bearing, but it reflects the processing method of the bearing. The chamfer is black, indicating that it has undergone heat treatment such as quenching, which increases the hardness of the bearing, and some people think that the black chamfer is not good-looking because it has not been processed completely, which is also a misunderstanding.
Why do bearings fail?
General bearing failure is caused by these nine problems: insufficient lubrication, solid contamination, liquid contamination, installation error, indirect damage, material and production errors, improper bearing selection, expired lubricant, improper lubricant.
However, solid contamination, expired lubricant, insufficient lubrication, and improper lubricant are often the causes of bearing failure. It can be seen that the lubricant is very important to the operation of the bearing.
Among them, installation errors, liquid contamination, indirect damage and improper bearing selection are the second causes of bearing failure. Among them, improper selection of bearings may be caused by problems of design, size and load capacity.
In the end, bearing failure caused by material and production errors is very rare. From this, we conclude that regular maintenance is essential for bearing operation.
If the lubricant is the cause of the bearing failure, these symptoms are generally present: discoloration of rolling elements and raceways (blue/brown), excessive wear of rolling elements, rings and cages due to overheating and catastrophic failure wear and tear. The reason must be that the lubricant flow is limited, and the high temperature reduces the quality of the lubricant. To solve this problem, we can use the right amount of lubricant, ensure proper bearing fit and control preload to reduce bearing temperature.
